分类目录

功能

Hal influenza A virus infection (Fig. 1A) as well as in

Hal influenza A virus infection (Fig. 1A) as well as in a previous study [6]. Our data and the previous reports suggest that FasL mediated signal in lung has a negative effect for protecting host against PR/8 virus infection. Since the same perspective was provided by the assay using the administration of a recombinant chimeric protein inhibitor for FasL/Fas interaction (Fig. 1B), this effect was not due to the other effects mediated by gld/gld mutation or genetic background before the viral infection. In Fig. 2, it is demonstrated that the severity of illness, such as GGTI298 biological activity reduction of body weight and survival 1531364 rate, after influenza A virus infection should correlate with the initial infected titer of the virus but not the titer of the propagated virus in the lung. In this situation, it was shown that induction of FasL gene in lung of mice lethally infected with PR/8 virus was detected earlier than in that of non-lethally infected mice, and this time-course kinetics seemed to correlate with loss of body weight (compared with Fig. 3A versus 3E, and Fig. 3C versus 3F). In addition, it was reported that activation of the Fas signal causes severe inflammation in the lungs of mice [7,8]. Although the series of immunological or pathological reactions in the host are triggered by the viral infection, our findings suggest that the severity of influenza should be regulated by the host reaction associated with FasL expression, especially in the early phase of the infection. Since it was demonstrated that gld/gld mutation prevented the reduction of the survival rate(Fig. 1) but did not affect the virus titer in lung (Fig. S1), this perspective is strongly supported. Regarding the molecular function of FasL in lung inflammation mediated by lethal infection with PR/8 virus, it is known that FasL plays an effector role in killing the virus infected cells as well as the activated lymphocytes [2]. The reduction of CD3(+) T-cell GS-9973 biological activity population in the lungs of mice infected with a high titer of PR/ 8 virus was observed and this reduction was prevented by gld/gld mutation (Fig. S2 A and B). These data and previous report [22] suggested that the FasL/Fas signal should negatively regulate the host protection system by controlling the T-cell population rather than eliminate virus-infected cells in lethal influenza virus infection. In Fig. 4, it is demonstrated that in non-infected mice, Fas protein was expressed on several cell surfaces, but expression of FasL protein was detected on a rare population of lung cells. In B6 mice lethally infected with PR/8 virus, it was observed that expression of FasL was dramatically increased on several cell surfaces but Fas expression was not or slightly up-regulated. More importantly, this induction of FasL expression due to lethal infection was not observed in B6-IFNR-KO mice. These findings indicate that the FasL/Fas signal should be triggered by the induction of 1317923 expression of FasL rather than Fas in mice infected with influenza A viruses, and this induction was regulated by typeI IFN mediated signal. Since, in the lung of control B6 mice lethally infected, higher induction of FasL expression in CD4(+), CD74(+), NK1.1(+) or CD11c(+) cells than other cell types was detected (Fig. 4, upper panel, light green color histogram), these cells should associate with the FasL mediated reduction of CD3(+) cell population in lung of mice lethally infected (Fig. S2). As shown in above studies, there are differences in kinetics of FasL mRNA e.Hal influenza A virus infection (Fig. 1A) as well as in a previous study [6]. Our data and the previous reports suggest that FasL mediated signal in lung has a negative effect for protecting host against PR/8 virus infection. Since the same perspective was provided by the assay using the administration of a recombinant chimeric protein inhibitor for FasL/Fas interaction (Fig. 1B), this effect was not due to the other effects mediated by gld/gld mutation or genetic background before the viral infection. In Fig. 2, it is demonstrated that the severity of illness, such as reduction of body weight and survival 1531364 rate, after influenza A virus infection should correlate with the initial infected titer of the virus but not the titer of the propagated virus in the lung. In this situation, it was shown that induction of FasL gene in lung of mice lethally infected with PR/8 virus was detected earlier than in that of non-lethally infected mice, and this time-course kinetics seemed to correlate with loss of body weight (compared with Fig. 3A versus 3E, and Fig. 3C versus 3F). In addition, it was reported that activation of the Fas signal causes severe inflammation in the lungs of mice [7,8]. Although the series of immunological or pathological reactions in the host are triggered by the viral infection, our findings suggest that the severity of influenza should be regulated by the host reaction associated with FasL expression, especially in the early phase of the infection. Since it was demonstrated that gld/gld mutation prevented the reduction of the survival rate(Fig. 1) but did not affect the virus titer in lung (Fig. S1), this perspective is strongly supported. Regarding the molecular function of FasL in lung inflammation mediated by lethal infection with PR/8 virus, it is known that FasL plays an effector role in killing the virus infected cells as well as the activated lymphocytes [2]. The reduction of CD3(+) T-cell population in the lungs of mice infected with a high titer of PR/ 8 virus was observed and this reduction was prevented by gld/gld mutation (Fig. S2 A and B). These data and previous report [22] suggested that the FasL/Fas signal should negatively regulate the host protection system by controlling the T-cell population rather than eliminate virus-infected cells in lethal influenza virus infection. In Fig. 4, it is demonstrated that in non-infected mice, Fas protein was expressed on several cell surfaces, but expression of FasL protein was detected on a rare population of lung cells. In B6 mice lethally infected with PR/8 virus, it was observed that expression of FasL was dramatically increased on several cell surfaces but Fas expression was not or slightly up-regulated. More importantly, this induction of FasL expression due to lethal infection was not observed in B6-IFNR-KO mice. These findings indicate that the FasL/Fas signal should be triggered by the induction of 1317923 expression of FasL rather than Fas in mice infected with influenza A viruses, and this induction was regulated by typeI IFN mediated signal. Since, in the lung of control B6 mice lethally infected, higher induction of FasL expression in CD4(+), CD74(+), NK1.1(+) or CD11c(+) cells than other cell types was detected (Fig. 4, upper panel, light green color histogram), these cells should associate with the FasL mediated reduction of CD3(+) cell population in lung of mice lethally infected (Fig. S2). As shown in above studies, there are differences in kinetics of FasL mRNA e.